Motor-control system



Dec. 30, 1930. H. L. VAN VALKENBURG MOTOR CONTROL SYSTEM F iled Oct. 19,1926' 2 sheet -sheet;

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H L. VAN VALKENBURG MOTOR-CONTROL SYSTEM Fi led Oct. 19, 1926 Dec. 30,1930.

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i Patented Dec. 30, 1930 UNITED STATES A ENT OFFICE I HERLION L, VANVALKENBUBG, OF WAUWATOSA, WISCONSIN, ASSIGNOR, BY MESNE ASSIGNMENTS, TOSQUARE 1) COMPANY, OF DETROIT, MICHIGAN, A CORPORATION all gearedtogether, the controller both caus-v {so as to brin the has et toconvenient posi-.

ings, in which or MICHIGAN MOTOR- CONTROL SYSTEM Application filedOctober 19, 1926. Serial No. 142,626.

tates first in one direction for a certain period and then in theopposite direction for a 'period. One of the objects of the invention isto .provide a unitary system in which the motor, the machine and thecontroller are ing the reversal of the machine and reversing with it.This obviates the need of a separate motor for rotating the drum.Another object is to provide a type of apparatus. in which thecontroller may overrun without harm therebydoing away with the need of aSlip clutch or similar protective device. A

further object is to provide simple means by I which the machine ma bejogged or inched tion for loa ing and unloading. Still an other objectis to 'provide simple and efficient apparatus in which the motor currentis handled entirely b means of main switches So that the contro er doesnot have to carr a heavy .current. i I accomplish these objects by themechanism illustrated in the accompanying draw- Figure 1 is a generalview largely diagram- 'matic in its nature showing the general assembly,including the washmg machine, motor, main switch, drum controller indeveloped form, and the hand switches and push buttons.

Figures 2 to 6.are diagrammatic views showmg the drum controller indifferent positions. Like numerals denote like parts throughouttheseveral views.

In the illustrated form the washing machine has a cylindrical basket 10journaled in a frame12 and enclosed within a tub or container 14 intheusual manner. The basket has a door 16 through which the machine may beloaded and unloaded. Power is supplied gears of the train there isfastened a shaft 22 provided with a pulley 24 connected by a belt 26 toanother pulley 28 fastened to a shaft 30 provided with a worm 32 whichmeshes with a worm gear 34 fastened to the main shaft 36 of the drumcontroller.

In the drawings the controller is shown in developed form, that isin theflat.- The drum 38 is provided with a reversing segment R, a forwardholding segment i and a backward holding segment g. In line with thesegment R at one side are two fingers 40, 42 and at the other side aretwo fingers 44, 46. In line with the segment 7 are two contact fingers48, 50, and'in line with the segment 9 are two contact fingers 52, 53.The contact fingers are stationary while the segments R, f, g rotatewith the drum in the usual manner. 1

The drum controller just described constitutes the master switch. I willnow describe the main switches through which the main energizingcurrents are carried to the motor:

In the form illustrated a three-phase system is employedhaving threemain conductors A, B, C. These are connected to stationary contactso60,62, 64 adapted to be engaged by switch arms 61, 63, 65 respectively.

These arms are controlled by a rod 66 which is longitudinally movableand is urged by a spring 68 to hold the switch arms in open position asshown in Fig. 1. For identification this will be termed the forward.main switch. The arm 61. is connected by a conductor 70 to a conductor71 constituting one of the motor leads. Arm 63 is connected by aconductor 72 to a conductor .7 3 which constitutes another of the motorleads, and arm 65 is connected by a conductor 74 to a conductor 75 whichconstitutes the third motor lead. ;Foroperating the machine in thereverse direction there is what may be termed a backward or reverse mainswitch. This includes three switch arms 76, 77, 78 which are connectedrespectively to the conductors 75, 73, 71. The arms are adapted toengage contacts 80, 81, 82 respectively which are conne cted byconductors 83, 84, 85 to the contacts 60, 62, 64 respectively. Said armsare operated by a switch rod 86 which is urged by a spring 88 to holdthe switch arms open.

Switcharm 66 is controlled by a winding F, one end of which is connectedby a conductor 90 to the main supply conductor A. A movable core 91 islocated within the field of winding F and is connected to rod 66 withthe result that when the winding is energized, the switch arms 61', 63,will close. The other end of winding F is connected by a conductor 92 toa stationary contact 93 which is connected by a conductor 94'to thefinger 40 on the drum. The circuit through the winding may be completedthrough the re versing segment R and finger 42 by'a conductor 96 whichisconnected to a conductor 97 connected to the finger 48. Said finger isconnected to the finger 50 by the holding segment f. A conductor 98connects finger 50 with a conductor 99 which leads to the switchterminal 100 of the hand-operated change switch E. The other terminal101 of this switch is connected by a conductor 102 to a conductor 103which is connected to a hand-operated service switch D. The stationarycontact 104 of this service switch is connected by a conductor 105 tothe main line conductor C.

The switch rod 86 is controlled by a winding G which controls a movablecore 110 fastened to the rod in such manner that when the winding isenergized the switch arms 76, 77, 78 will close. A conductor 112connects one end of winding G to the conductor 83. At the opposite endthe circuit through the winding is completed by a conductor 113 whichleads to a, contact 114 which is connected to a conductor 115 whichleads to the finger 44. The reversing segment B may connect the finger44 to the finger 46 which is connected by a conductor 116 to a conductor118 which is connected to finger 53. This finger may be connected byholding segment 9 which is connected to conductor 99 which leads to themain supply conductor C in the manner previously described. The forwardmain switch rod 66 is connected to and operates a holding switch 120which is connected to conductor 96 and is adapted to engage contact 93.The backward switch rod .86 is connected to and operates a holdingswitch 122 which is connected to conductor 118 and is adapted to engagecontact 114. These holding switches 120, 122 are closed by the switchrods at the same time that the main supply switches close.

Now to describe the switches by which the motor may be started or bywhich it and the basket of the washing machine may be jogged or inchedwhen necessary for loading or unloading: For inching, the drumcontroller is put out of service by opening the change switch E and thenclosing the circuit for one or more short periods through the motor tocause it to rotate the required amount. This is done by momentarilyclosing the forward or backward main switch, as the case may be. Torotate the motor backwards the operator closes the normally open pushbutton 130 which is connected to the conductor 102 and .is adapted whenclosed to engage'the contact 142 which is connected by a conductor 144to conductor 94. I r Y Operatz'0n.Let it be assumed that the motor is atrest in its mean position and the various switches open and the drumcontroller in approximately neutral position, all as shown'in Figure 1.If now the operator wishes to start up the motor and cause the machineto operate automatically, in distinction to inching, he closes serviceswitch D and change switch E and presses one of the push buttons 130 or140. It is immaterial in which direction the machine starts to rotate,and to conform to the selected diagrams let it be assumed that he wishesthe machine first to rotate backward. He pushes button 130 to closedposition whereupon the winding G is energized and closes the switch arms76, 77,78, which energizes the motor and causes it to rotate in what maybe termed a backward direction.

The winding is energized as follows: from supply conductor A to contact60, to conductor 83, to conductor 112, to winding G, to conductor 113,contact 114, conductors 115 and 132, contact 131, push button 130,conductor 103, switch D, contact 104, conductor 105 and main supplyconductor C. The movement of the switch rod 86 to closed position closesthe holding switch 122 and thereafter the windingG is kept energized asfollows: from supply conductor A to contact 60, conductors 83 and 112,to winding G, thence by conductor 113, contact 114, holding switch 122,conductor 118, finger 53, segment g, finger 52, conductor 99,- contact100, switch E, c0nductors 102, 103, switch D, and conductor 105 to mainconductor C. As the motor rotates it displaces the drum from the meanposition shown in Figure 1 toward the left to the position shown inFigure 2 where the segment g has moved out of engagement with thefingers 52, 53, thus opening the circuit through the winding G andpermitting sprin 88 to open the main switch and incidentafl open theholding switch 122.

The motor current is now cutoff but the motor will continue to drift andfurther displaces the drumcontrollcr'to the position shown in Fig. 3 inwhich the reversing segment R- engages the fingers 40, 42 whichcompletes the circuit through the forward winding F in the followingmanner, it being understood that the holding segment f still remains inengagement with" the fingers 48,

50; from the supply conductor .A to conductor 90 to winding F, thencethrough conductor 92, contact 93, conductor 94, finger 40, segment R,finger 42, conductors 96 and 97,finger 48, segment f,finger 50,conductors 98, 99, switch E,-conductors 102 and 103, 7

switch D, and conductor 105 to the supply conductor C. As a result ofenergizing the winding F the forward switch arms 61, 63, 65 close andsupply the motor, the phase relation being changedand the motor rotatingin the opposite or forward directionv-The closing of the forward switchincidentally closes the holding switch 120, with the result thatthereafter the winding F is kept energized through the followingcircuit: From conductor A to conductor 90 towinding F, thence toconductor 92, contact '93 holding switch arm 120,- conductors 96 and 97,finger 48,segment f, finger :50, conductor 98, conductor 99, switch E,conductors 102 and 103, switch D and conductor 105 to the 2a supplyconductor 10. F

' As the motor is now reversedit will cause the washing machine and thedrum controller to rotate inthe opposite direction and they controllerto move; toward the right from the position :shown in Figure 3 to theposition shown in Figure 4. This latter figure shows the drum after ithas rotated the major portion of its normal travel. The segment fhasleft the fingers 48, 50,-thus opening the 35 circuit through the windi F'and incidentally opening'the holding switch 120. The spring 68now'opens the forward switch arms 61, 63, 65, thus cutting oil themotor,

which however continues to drift-until the position shown in Figure 5 isreached, where the, reversing segment [It has reached the fingers 44,46. The segment g, however, still remains in contact with the fingers'52, 53. Thereupon the motor will begin to work for the winding G willbeenergized as fol-- I, lows: from the supply conductor A, contact, "60,conductors 83 and 112 to'the winding, G, thence through the conductor113, contact 114, conductor115, finger 44, segment R, finger 46,conductors 116 and 118, finger 53, segment g, finger 52, conductor 99,switch E, conductors 102 and 103, switch D, and conductor 105 .to themain line. conductor C.

The closing=of the main switch closes the holding switch 122, which willkeep the winding Genergi'zed-in the manner previously:

described. Thus itwill be seen that-the mo? tor is-caused to rotatealternately inoppositedirections for-a predetermined number of rotationsand -the action will be entirely automatic after the push button; hasbeen. pressed for starting the system.

IIt will be noted that-either ofthe push buttons 130 or 140 may beemployed for starting up the apparatus after the switche's D and E havebeen closed. 'The closing of the I switch 140 will cause the ener'zation of winding F-to start the motor in a orwarddilrection in thefollowing mariner: from: the .supply conductor 'A to the" conductor .90and coil F thence through the'conductor 92 .to the 142, switch 140,conductor 10?), switch D, and

Contact .93, conductors 94 and 144, contact conductor 105 to the'supply' conductor C.

Afterthis coil F is onceenergized it closes the holding switch 120 whichthereafter-keeps the" coil energized so long as-the'segment remains incontact with the fingers-48, 50.

greater or less distance, as the case may be, to bring-thedoor 1.6 toproper position] for inserting or removing the'clothing, or" other goodsto be treated; -This supplemental ro-- I tar-y movement or*inching willbeaccom- 'to'changing from automatic to hand control. Suppose that hewishes the machine then to Assume now that the washing operation iscomplete, and'that the washing machine is to be unloaded. Ordinarily itwill be necessary torotatethe basket'gforward orbackward a open thechange-switch E as a preliminary 'move forward a'short distance. He willI press the push button '140 which will energize the forwardcoil- Fasfollows:

From the supply conductor A to the conductor 90, to coil F,thencethroughconductor 92 to contact 93, conductor 94, conductor 144,

contact 142, switch140, conductor 103, switch D, conductor -105 throughthe main supply conductor 0. Energizing the winding will close the mainswitch arms 61, 63, 65. The

operator will hold the hand switch closed only'for a moment, which willjog the motor forward. Hthe movement is insuflicient the action can berepeated. If instead of de.-'

siring the machine to move forward the operatorwishes it to movebackward, he will 3 press the push button 130 which will energize supplyconductor A to contact 50, to eonduc and 132, contact 131, switch130,"conductor 103, switch D and conductor to the main conductor C. Thisswitch 130 will be held.

closedonly' momentarily forrone or more the backward coil G as follows:from the tors 83 and 112, to the coil, thence through conductor.113,contact 114,conductors times although after an operator becomesexperienced he may be'able' to estimate the of the basket.

In the form shown, is designedto rotate about 180 degrees, first in onedirection and thenin the other. 'Ilhere may be occasions, however, whenthe motor" will cause the drum controller to Qverrun: For example, ifthe operator cuts ofl the current by opening the switch E 'at a'momentj.when the parts arein a position-su'chas that illustrated in Figure 4where the reversing.

amount of time the push buttonswitch must be heldclosed to cause the.desiredmovement he drum controller segment R is near the end of itstravehbut drift for a considerable distance, for instance,

to a position such as that shown in Figure 6. But no harm will be done,for the motor may 'be jogged independently of the drum controller, thatis, by using the push buttons 130 or 140 in the manner alreadydescribed. If the operator wishes to recommence automatic operation allhe will have to do will be to hold one of the push buttons closed longenough to cause one of the segments f or g to engage their cooperatingfingers. Thus the drum controller is not required to have any definitestopping point and there is no need of a slip clutch or similar devicefor protecting the applaratus from wrecking itself.

aving thus described my invention, what I claim as new and desire tosecure by Letters Patent isi 1. In a system for driving and periodicallyreversing a rotatable body, an electric motor .for driving said body,magnetic switches, one

for causing the motor to rotate forwardly and the other backwardly, arotatable controller connected to said body to rotate therewith, thenormal zone of operation of the controller being less than a completerevolution, and

' means controllable at will and independent of the controller forinching the motor to bring the controller back into the zone ofoperation in case it should over-travel.

2. A system for driving and periodically reversing arotating body havingan electric motor connected to said body for driving it, a pair ofmagnetic switches, one for causing the-motor to rotate forward and theother backward, a drum controller for operating said switches, means forrotatingthe drum first in one direction and then in the oppositedirection in synchronism with the rotating body, the drum having anormal zone of operation which is less than a complete revolution, andan inching switch arranged in parallel with the drum controller forholding .a main switch closed and thereby causing rotation of the motorindependently of the drum whereby if the drum has rotated past itszoneof operation the inching switch can be employed to bring it back.

3. In a reversible motor controlling sysrotatable drum controllermechanically connected to the motor for reversing rotation therewith,said controller having a pair of holding segments for maintaining eachand operating circuit of a said switch, said seg ments being arrangedcircumferentially of the controller, the opposed ends of the se mentsbeingarranged in overlapping and in spaced relationship, and a reversingsegment arranged in the circumference of said controller at a pointopposite the space between the spaced ends of said holding segments.

' 4 In an electric power system for driving and periodically reversin arotating body, a motor connected to said body for driving it in eitherdirection, a main switch for operating the motor forwardly, a secondswitch for reversing the motor and a movable controller connected to therotating body, and movable forwardly and backwardly in synchronism withit, a circuit for operating said main switch, and a second circuit forcontrolling said reversing switch, said controller having a pair ofelongated holding segments with spaced apart ends and arrangeable, eachin one of said operating circuits to close the same, and ashorterreversing segment rotating intermediate the ends of the holding segmentsfor normally energizing one or the other of said operating circuits, theoperation tem, a motor, a switch for causing the motor A

